CZ + cast = nope

[chris in va]

After all this cast boolit frustration with my CZ, I finally realized the chamber isn't the same as my other 9mm's.

Got my 358-125 mold going and sized them down from an as-dropped 362 to 358. Still won't chamber. I tried them in my HiPoint carbine and Kahr, slide in all they way out to 1.075oal! The CZ won't even consider it until about 1.015.

At this point it looks like I need to get the chamber reamed some if I want to shoot cast out of it. The boolit will stick on the sharp transition between the chamber and rifling, whatever that is called. Just eyeballing it I can see it's thicker than the others.

I can go with a smaller boolit, but then all accuracy is lost and I get tumbling.

[Echo]

Well, I wouldn't alter the chamber - it seems that you have a minimum chamber, or maybe a standard chamber! After all, the 9 is supposed to have a .355 groove diameter, and a .358 boolit may be too fat. Try sizing down to .357 and see if they will chamber then. If not, down to .356 - if not then, there is a problem. But I'll bet .357 will work. Be aware of the brass you are using, too. Some headstamps may chamber w/.358 boolits.

FWIW, I size my 9mm boolits to .358, and they work fine in my P1. But one must listen to Professor Gun - if PG says 'NO!', then one must do PG's bidding. They won't chamber in my BHC, but .357's will.

[HeavyMetal]

Sound like the chamber wasn't throated properly.

Any good gunsmith should be able to do this for you and, if fairly new, CZ should take care of this under warranty.

[mike in co]

Sound like the chamber wasn't throated properly.

Any good gunsmith should be able to do this for you and, if fairly new, CZ should take care of this under warranty.

FIX THE PROBLEM, NOT THE SYMPTOM

wrong...he is shooting too big of a bullet for the chamber.....


cz'S have a great rep for accuracy out of the box.


so what cz do you have ?

consider sizing down( as in get a 9mm mould and not a 38/357 mould) TRY 356....

[zomby woof]

My CZ 75 loves 147 TC boolits.

[chris in va]

I get so many opinions, and they all conflict.:veryconfu

Started with a 124gr 9mm TC... keyhole.

Was given some 147gr 9mm FN...keyhole.

Suggested I get the 125gr 358 RFN, but the ogive is very short and won't chamber. It drops at .362 so I bought a 358 sizing die.

None of these will chamber unless loaded very short OAL, enough that I have to drop powder at bare minimum levels.

I'm really leaning toward getting the barrel reamed at this point. It's the only gun I have with the problem.

The 75 has zero problems with FMJ/JHP, and I suspect it was designed for ONLY that type of bullet.

[JRR]

I would start with a "semi wadcutter" round nose or mild flat point designed mould. You need a bullet with a reduced nose diameter and not the inner case diameter. I believe RCBS makes a mould like this. I know they make it for the 40 S&W. You might call it a semi bore rider design. The 40 version works great in my CZ SA.
Jeff

[35remington]

There's a difference between a chamber that doesn't allow a longer overall length and one that won't accept a fatter bullet.

A short chamber may accept a fatter bullet. A longer chamber may not tolerate a fat bullet while allowing a longer overall length.

Ideally, you'd have a gun that would allow a long enough overall length to chamber your bullet of choice at a reasonable seating depth while also allowing a fat enough bullet that exceeded the barrel's interior diameter measurement.

I'd suggest an inexpensive Lee RN mould for the 9mm to avoid throat engagement and seating depth issues. I'm thinking of the 356-125-2R or maybe the TL356-124-2R if the front band is seated almost entirely in the case, which shouldn't make seating depth too great. If you want to get a mould that casts on the larger end of the tolerance range, send Lee a check and have them select one that does......they've done this for me in the past. Even if designed for jacketed, it's possible to find something that fits. Look for a bullet that has a proper length while having a short full caliber section that allows reasonable seating depth while having little full caliber diameter sticking out of the case to prevent engaging the short throat.

The Lee moulds are so inexpensive that it's a better option that reaming the chamber right away. If the gun shoots jacketed really well, you might want to hesitate before you try altering it.

Usually keyholing bullets are symptomatic of undersized diameters. Usually.

[mike in co]

so first measure the boolits that are supposedly 358..are they or arent they ?

next nose profile...find onre that is close to fmj profile.

while not ideal an oal of 1.015 that chambers freely could be ok.

just remember that means less case volume and less powder for a given velocity.

bullseye will get it over 1000 fps.

you are going thru the same thing i just did with my 45's.

my orignal commercial boolit worked well but when i tried to cast my own....big differences in oal for the two guns, and liek you i wanted one load, one oal for both( this does not always provide best accuracy in both). so i sold that mould and bought another....cast , tried and was lucky second one provided what i needed. not ideal, but what worked.

lots of bullet will seat out to 1.150 or more in my cz's....
so i suspect your bullet choice and or dia.
did you slug the bbl ?
whenyou use an oal of 1.075 whats hitting..boolit nose od or boolit body od ?
mike in co

[putteral]

What powder are you using when you get tumbling? If you are using a fast burning powder that might be the problem. In 9mm I switched to slower burning powders. Power Pistol,Unique and AA#5. All 3 stopped my tumbling problems. Was using Titegroup& Bullseye.

[GabbyM]

My S&W won't take a .357” bullet into the throat. Not an issue with the Smith since the bore is .3545” just like new. I size even the ball profile round nose bullets to .356” for that gun. Remember the throat will size any bullet shot down it so bullets are never going down the barrel at a larger diameter than the throat. With 9mm and 40 S&W I like a BHN #15 or harder bullet.

[Dan Cash]

I suspect that this might be one reason the truncated cone bullet was used in early Parabellum ammunition. I used to have a Lyman mould that threw 125 grain TC bullet. Seated exactly to the point where the cone taper began it fed flawlessly in a Star B, P38 and a Luger. CZ was not around in those days.

[Cherokee]

Lyman 356402 is the 120'ish gr, long nosed TC bullet that should work fine for you. Works for me.

[runfiverun]

this is not fixing his problem.
seating deeper seems to let the 358 sized boolit chamber fine.
you probably just have a different throat cut into the cz.
it's like using a loverign loved by everybody in their 03 0-6's, in a savage 110 with the throat cut for jaxketed.
not gonna chamber unless the loverign is seated below the neck by about 2"s.
if it won't feed when it is hitting the feed ramp on the way into the bbl.
causing an issue there.
if it won't work it won't work, an auto loader has to feed everytime no matter what. or it is no good i.m.o.
you either need a mold that does work or go another route with this particular pistol.
you ain't the only one with a mold for just one gun trust me.

[mike in co]

I suspect that this might be one reason the truncated cone bullet was used in early Parabellum ammunition. I used to have a Lyman mould that threw 125 grain TC bullet. Seated exactly to the point where the cone taper began it fed flawlessly in a Star B, P38 and a Luger. CZ was not around in those days.


your cz may not have been around, but cz has been around.....since 190something if not before.

.....thier site says 1936, but i know there are cz pistols data prior to '36

[sniper7369]

you ain't the only one with a mold for just one gun trust me.

For sure. I have a Lee 356-120-TC that will only work in my Springfield EMP sized at .357 Every other 9mm I own refuses to chamber the loaded rounds.

[sagacious]

The LEE 356-120-TC shoots great in the stock barrels in my CZ 9's. With that bullet properly sized and properly seated (to the edge of the ogive), OAL cannot present a chambering or failure-to-enter-battery problem.

Best of luck. :drinks:

[sniper7369]

The LEE 356-120-TC shoots great in the stock barrels in my CZ 9's. With that bullet properly sized and properly seated (to the edge of the ogive), OAL cannot present a chambering or failure-to-enter-battery problem.

Best of luck. :drinks:

I think my other pistols may need that boolit sized down to .356, the EMP leaded pretty badly with the TC sized at .356 but when I bumped it up a thousandth all leading stopped and groups tightened right up. Tried the same ammo in an M&P and a PT-99 and the boolit sticks in the chamber so tight it locks up the slide. While trying to unlock the slide on the M&P the boolit was actually pulled from the brass and powder spilled when it opened up.
My 365-102-1R sized at .357 does work in those pistols though. [smilie=b:

[ChuckS1]

I have a CZ-75 pre-B that I bought in Germany in 1987. I replaced the OEM barrel with a Bar-Sto barrel not long after I bought it since the accuracy was only so-so with factory ammo. It shoots best with a Lyman 358242 125 grain boolit sized to .357 and 3.5 grains of Bullseye. That load will stay right about 2" or so at 25 yards.

Chris, don't know what part of Virginia you're in, but Hatfield Gunsmithing in Manassas can fix that ramp problem you have. He's a former AMU gunsmith and specializes in custom pistol work.

[finishman2000]

I had the same problem with my EAA CZ silverteam in 9mm. It had not enough throat. My local smith fixed it very quickly and now fine. I size my 9mm heads .357

The 9x21 barrel was fine from the start.

[rwt101]

After all this cast boolit frustration with my CZ, I finally realized the chamber isn't the same as my other 9mm's.

Got my 358-125 mold going and sized them down from an as-dropped 362 to 358. Still won't chamber. I tried them in my HiPoint carbine and Kahr, slide in all they way out to 1.075oal! The CZ won't even consider it until about 1.015.

At this point it looks like I need to get the chamber reamed some if I want to shoot cast out of it. The boolit will stick on the sharp transition between the chamber and rifling, whatever that is called. Just eyeballing it I can see it's thicker than the others.

I can go with a smaller boolit, but then all accuracy is lost and I get tumbling.

What model CZ do you have?
Bob T

[mike in co]

I had the same problem with my EAA CZ silverteam in 9mm. It had not enough throat. My local smith fixed it very quickly and now fine. I size my 9mm heads .357

The 9x21 barrel was fine from the start.

an eaa is not a cz..by a long shot.....( yes its a clone..but it aint a cz...and yes i own an eaa)

and again you fixed a sympton, not the problem.

if its ok with you then fine,,,,,,

mike in co

[prickett]

After all this cast boolit frustration with my CZ, I finally realized the chamber isn't the same as my other 9mm's.

Got my 358-125 mold going and sized them down from an as-dropped 362 to 358. Still won't chamber. I tried them in my HiPoint carbine and Kahr, slide in all they way out to 1.075oal! The CZ won't even consider it until about 1.015.

At this point it looks like I need to get the chamber reamed some if I want to shoot cast out of it. The boolit will stick on the sharp transition between the chamber and rifling, whatever that is called. Just eyeballing it I can see it's thicker than the others.

I can go with a smaller boolit, but then all accuracy is lost and I get tumbling.

I shot the same bullet yesterday in my CZ-75. My slugged barrel measured .354 and I was using .356 diameter bullets. I also sized some .357 bullets for my SIG Sauer and tried them - successfully - in the CZ as well.

Be aware that the chambering problem might be OAL rather than bullet diameter. Two weeks ago, about 75% of the cartridges failed to go to battery due to the OAL being too long. This week I seated the bullets so that forward most grease groove was fully covered by the case and chambering was perfect.

[GabbyM]

I'd say the bullet should fit into the throat. Then if the throat is smaller than your bore you have a problem that needs remedied.

As I stated in my post above My S&W-659 throat will not take a .357” bullet. However the barrel measures just under .355” so .356” bullets work. After all a 9mm is supposed to have a .355” barrel to shoot .355” jacketed bullets. We have become so accustomed to oversized European bores it would seam some think something is wrong when you can't shoot an oversized bullet.

You need to measure your bore to start then figure out what the issue is with tumbling.
IMO if you properly fit your bullet cast at BHN #14 or harder then charge laods with a powder of WW231 or slower to at least 1050 fps it should shoot. some real lube in the groves like LARS carnauba red or felix lube is a nessesity as I've had absolutely no luck with the hard lube in comercial bullets I've bouhgt in past days. I've shot Jakes hard lubes that work and their are others but the ones made of wax over wax with no oil just don't cut it.

[leftiye]

Do a chamber cast! Then you will KNOW what the chamber looks like. Then maybe alter it to be like you want. One way or the other that chamber ain't right. After all - if a standard 9mm round won't fit what else is there?

[sagacious]

While trying to unlock the slide on the M&P the boolit was actually pulled from the brass and powder spilled when it opened up.

Are you using the TL356-124-TC, or the 356-120-TC?

Sounds as though you might be using the TL 124TC.

Seated to the edge of the ogive, the LEE 120TC leaves no bearing surface at all for the rifling/leade to contact. There are several potentially critical differences between these two designs, and the absence of exposed bearing surface on the 120TC seated to the edge of the ogive is one of it's strengths.

Good shooting. :drinks:

[ScottJ]

I have very limited cast experience with the CZ 75B I picked up used last year.

I've only tried the RCBS 115gr truncated cone (they call it round nose) seated to 1.095 OAL (which is fairly deep for the design) over 3.8gr Bullseye.

Only put a couple of magazines of them through the CZ. The leading was light and came out like glitter when I pulled a bore snake through. Accuracy was good.

[mpmarty]

My EAA Elite Match shoots the LEE 170gr TCTL just fine with the factory 10mm and 40 S&W barrels. Boolits are tumble lubed as cast and come out at .401. I use a heavy charge of Red Dot over a Wolf LP primer.

[jbremount]

After all this cast boolit frustration with my CZ, I finally realized the chamber isn't the same as my other 9mm's.

Got my 358-125 mold going and sized them down from an as-dropped 362 to 358. Still won't chamber. I tried them in my HiPoint carbine and Kahr, slide in all they way out to 1.075oal! The CZ won't even consider it until about 1.015.

At this point it looks like I need to get the chamber reamed some if I want to shoot cast out of it. The boolit will stick on the sharp transition between the chamber and rifling, whatever that is called. Just eyeballing it I can see it's thicker than the others.

I can go with a smaller boolit, but then all accuracy is lost and I get tumbling.


I am not an CZ expert, but FWIK, I would not get the chamber reamed. CZ pistols are made short chambered this way for a reason. This is not by accident or sloppy machining. It may seem an additional pain in the rear, to fit the bullet to the short chamber of the CZ, but no one has ever accused CZ guns of not being accurate.

Anyway, the link below is a good info on what I think is the the "very same" topic. Maybe this will help you get closer to the answer of your questions and problems.

Go to this site and read this post....http://www.czforumsite.info/index.php?topic=29504.0




...

[chris in va]

That's the thing though, I can't "fit the bullet to the short chamber" because the ogive catches on that sharp transition between the chamber and where the freebore starts (someone please tell me what that's called). Even my .355 sized boolits do this. The only ones that don't are the FMJ that measure .348 at the case mouth.

[sheepdog]

My CZ 75 loves 147 TC boolits.

As does mine (180s though, I got the 40 cal).

[jbremount]

That's the thing though, I can't "fit the bullet to the short chamber" because the ogive catches on that sharp transition between the chamber and where the freebore starts (someone please tell me what that's called). Even my .355 sized boolits do this. The only ones that don't are the FMJ that measure .348 at the case mouth.



I could be wrong here, but I am thinking you don't have a problem with the sizing of the bullets. The .358 size is fine. You are having to seat the bullet to what appears to be short OAL because of the truncated cone shape of the bullet. A trunacuted cone bullet will be shorter OAL especially in a CZ. I have that very same mold and a CZ-75b and my OAL is about 1.010-1.013. You said your gun began to chamber the bullet at 1.015. Maybe others with CZ guns will chime in with their OAL using bullets from the same mold as yours and give you an idea what they are using. I think they will also be similar OAL as yours.

You can also ask Angus at the CZ forum for a more/the best informed answer. send a picture of your bullet.

I read on the CZ forum that Angus was shooting his bullets at 1.010 OAL:http://www.czforumsite.info/index.php?topic=21371.0

[HeavyMetal]

The area your talking about, transition point from chamber end to rifling is called "leade".

Basically the rifling is supposed to taper from the end of the chamber to full rifling. It does this in a very short distance and I'm sure theres a formula to figure it out but have no idea what it is or where to find it.

In high power rifles "Freebore" is the area in front of the chamber that has had the rifling removed to reduce both pressure and allow a longer bullet to be used in the load.

In this case I think you have a chamber cut for standard 9mm diameter ball ammo and a larger than standard barrel.

Have a quality gunsmith adjust the "Leade" in your barrel is the only way your going to use the specific boolit you have in this particular gun.

I will refer all readers to Dean Grennell's book of the 9mm. It has very usefull information on pretty much every 9 that was available at the time it was written including the fact that each and every gun was fired with selection of both factory loads and hand loads.

Very interesting reading.

At the end of the book, and this is most important in this case, they took 4 pistols and fitted them with Bar-Sto barrels and did a comparo of before and after testing.

The CZ 75 used in the test was a dog! Call me what you will this particular gun couldn't shoot a 5 inch group with the best ammo on hand!

A switch to the Bar-Sto netted and impressive 75% to 80% improvement in group size!

Enough to suggest to me that CZ barrels, at one time, weren't really up to speed.

Depending on the age and many other factors this could be part of the problem with the gun the original poster is using.

After reading the book I figured any used CZ 75 I bought would automatically get a barrel change.

So far that opinion has not changed!

[mike in co]

I had the same problem with my EAA CZ silverteam in 9mm. It had not enough throat. My local smith fixed it very quickly and now fine. I size my 9mm heads .357

The 9x21 barrel was fine from the start.

what is a 9mm HEAD ????

[mike in co]

After reading the book I figured any used CZ 75 I bought would automatically get a barrel change.

So far that opinion has not changed!

I HAVE SEVERAL 9MM 's and TWO 9x21's

the 9's have stock cz bbls and shoot very well....from the 90's thru 2004/5.

the 9x21 are barsto for the match chamber.( some 9x21's are just 9x19 with the reamer pushed in an extra 2mm ..these leads to a large loose back end of the chamber)..

again i think it is silly to "fix" the bbl when the issue is one bullet mould.

he needs to ask for sample bullets of various designs,and try them . if 9mmball fits his gun, there must be a cast boolit that will do the same.

again, fix the probelm , not the sysptom.

mike in co

[Colorado4wheel]

That's the thing though, I can't "fit the bullet to the short chamber" because the ogive catches on that sharp transition between the chamber and where the freebore starts (someone please tell me what that's called). Even my .355 sized boolits do this. The only ones that don't are the FMJ that measure .348 at the case mouth.

I would be happy to send you some of my 147gr Lyman bullets that measure .356 and weight 155gr. Get you a small batch to test fit and then try and see how they shoot. Like I said a year or so back I think your chamber is out of spec. The bullets I would send you work fine in my KKM barrel @ 1.080" I think you should ream it and see if some of your current bullets would then work. Another option is to slug just the throat. I had a Lone Wolf barrel with a huge throat. It leaded with everything. Yours sounds like the exact opposite. Just because CZ's tend to run like this doesn't make it good. Not bashing CZ it's just kinda nice to have a gun that works rather then a gun we think would work great if I could only find the "one" bullet it likes.

[mike in co]

After all this cast boolit frustration with my CZ, I finally realized the chamber isn't the same as my other 9mm's.

Got my 358-125 mold going and sized them down from an as-dropped 362 to 358. Still won't chamber. I tried them in my HiPoint carbine and Kahr, slide in all they way out to 1.075oal! The CZ won't even consider it until about 1.015.

At this point it looks like I need to get the chamber reamed some if I want to shoot cast out of it. The boolit will stick on the sharp transition between the chamber and rifling, whatever that is called. Just eyeballing it I can see it's thicker than the others.

I can go with a smaller boolit, but then all accuracy is lost and I get tumbling.


did you ever slug the bbl on the cz ?

[chris in va]

Yes, it came out to .355.


again i think it is silly to "fix" the bbl when the issue is one bullet mould.

It's not one mold. I've tried 4 different bullet shapes and weights, all with the same issue. Unless the bullet ogive above the case rim is .352 or smaller, it gets caught on that edge and I have to load it with a short OAL.

[sagacious]

Yes, it came out to .355.

It's not one mold. I've tried 4 different bullet shapes and weights, all with the same issue. Unless the bullet ogive above the case rim is .352 or smaller, it gets caught on that edge and I have to load it with a short OAL.

Seems like you've tried all the solutions... except the one that will doubtless work:

The LEE 356-120-TC. Seated to the edge of the ogive, there is no ogival bearing surface at all, so no chambering problems. Shoots great in my EAA Witnesses.

What more is needed to solve the problem? Seems like a done deal.

[Colorado4wheel]

Seems like you've tried all the solutions... except the one that will doubtless work:

The LEE 356-120-TC. Seated to the edge of the ogive, there is no ogival bearing surface at all, so no chambering problems. Shoots great in my EAA Witnesses.

What more is needed to solve the problem? Seems like a done deal.

Maybe, maybe not. It could be a issue with the throat being the wrong size. He is keyholing with small boolets which is odd for a tight chamber. If his barrel and chamber are some odd mismatch he could find nothing works in this barrel right until he fixes the throat. He would be smart to slug the barrel and the throat seperately.

[sagacious]

Maybe, maybe not. It could be a issue with the throat being the wrong size. He is keyholing with small boolets which is odd for a tight chamber. If his barrel and chamber are some odd mismatch he could find nothing works in this barrel right until he fixes the throat. He would be smart to slug the barrel and the throat seperately.

Take a closer look at the picture of the LEE 356-120-TC.

That LEE bullet does not contact the throat. So, no problem with how the throat was cut. Cut long, cut short, doesn't matter.

As long as an empty 9mm case will fit in the chamber, a loaded round with that bullet seated properly into the case will fit. Chambering problems fixed.

Good shooting! :drinks:

[MtGun44]

Boolits not "heads", please.

[robertbank]

I have five CZs They are great guns but have exacting chambers. Size your bullets down to a max of .357 and load the cartrdges short. You wont have any problems with those bullets. I load 156 graineres from a mold that is supposed to drop them out at 137 grains. They run through my CZ like butter.

Cast is all I shoot in my CZ 9MM guns.

Take Care

Bob

[chris in va]

How does one slug the throat, exactly?

[HeavyMetal]

Chris:
In this case I don't think I'd "slug" the barrel or chamber, this is done by forcing a soft lead "slug" through them.

Instead I'd get some Cerrosafe from Brownell's. Cerrosafe is a metal alloy that has an extremly low melting point. Low enough that boiling water will melt it!

Clean the barrel extremly well and degrease with brake cleaner and then scrub with hot water and any good dish washing detergent in very hot water.

The barrel will most likely be squeaky clean after the detergent scrub and nice and warm which you need for a good casting of the chamber and leade area.

From the muzzle end push some cleaning patchs that fit very tightly into the barrel to the point just in front of where a bullet from a standard ball round would end.

Then pour the melted Cerrosafe into the chamber. Done as suggested this should give yu a casting that shows the entire chamber, the leade area and about a quarter inch of the rifling.

Once it hardens, and it will do that quickly, "pop" it up and out of the chamber from the muzzle end with a nice wood dowel.

Now you have a casting that shows everything going on inside the chamber of your particular barrel. If something is amiss a quality gunsmith can tell from looking at the chamber casting and make a suggestion as to how to fix it if it needs fixing.

I really think this is the only way you'll know whats up with this barrel.

Once that is determined you can decide if a special mold or a reamer is required.

Until then were all just guessing.

[Colorado4wheel]

How does one slug the throat, exactly?

I took a soft lead and just inserted it into the chamber and the very first part of the barrel. So like slugging the barrel but you stop before it leaves the chamber and back it back out.

[Colorado4wheel]

Take a closer look at the picture of the LEE 356-120-TC.

That LEE bullet does not contact the throat. So, no problem with how the throat was cut. Cut long, cut short, doesn't matter.

As long as an empty 9mm case will fit in the chamber, a loaded round with that bullet seated properly into the case will fit. Chambering problems fixed.

Good shooting! :drinks:

As long as your happy with a 120 gr bullet and spending even more on another mold when you already have four purchased for this gun.

[sagacious]

As long as your happy with a 120 gr bullet and spending even more on another mold when you already have four purchased for this gun.
Yup, works great in all of my 9mm's. Sometimes trying to reinvent the wheel isn't worth the hassle.

Since I load for 9mm's by S&W, Browning, H&K, Sig, Glock, EAA, and some older foreign pistols, I need a design that will work in all of them. It's too expensive and time-consuming to buy a stack of different molds for 9mm, so it just seems easier to go with a design that's going to chamber in all of them. All I need to do is size the bullet according to the specific 9mm, and load the amount/type of powder that works best.

The design and weight of the LEE 356-120-TC is almost identical to the Norma 9mm 123gr TC 'Safety Bullet', which was designed for use in a wide-variety of 9mm firearm models for police and security-force use. Simple, versatile, and works for me.

Best of luck! :drinks:

[Linstrum]

Hi, chris in va, since you are having such a problem getting your Cz to work like it is supposed to, I would do as HeavyMetal suggests and make a Cerrosafe casting to see the exact shape, surface condition, and dimensions of the chamber and first 1/4-inch or so of the rifling. The hardest part of doing that is waiting for the Cerrosafe to arrive from Brownell's. As has been mentioned already, Cerrosafe melts right around the boiling point of water and is easy to use after you get the barrel prepped and plugged to make the casting. Just a suggestion - I have found that the cloth patch material used to plug the barrel should be baked for about ten minutes in an oven at no more than 275ºF to drive off moisture and other volatile stuff to keep gas bubbling to a minimum since voids caused by bubbling may make taking measurements difficult.

In conjunction with making a casting I would also take advantage of what slugging the chamber area, the chamber and throat area, and then the ENTIRE length of the barrel will reveal. Doing all three will tell you what the cartridge besides the bullet encounter when they are in motion as the gun cycles. Slugging the entire barrel will give you the smallest diameter that the bullet encounters as it goes through the barrel and is important because you may have an unusual and therefor unexpected machining defect not obvious by casual inspection. When having the problems that you are encountering, it is best to inspect everything as much as is possible. There have been many good suggestions made and you should be able to discover the sources of your aggravation. I say "sources" since multiple problems seem to be the norm and I suspect that you have more than one thing wrong.

Pistols can be as accurate as a rifle, so keep working at it. I know this is aggravating, but you are also learning things that will help out the next time you have something not right. We were all in your shoes at one time or other!

I have a Cz85B I bought new about five years ago and it is a 2 to 3-inch at 25 yard shooter using the Lee 356-120-TC, and I can trust it to put a bullet where I want every time at that range. So there are good Cz pistols around.


rl778

[Buckshot]

http://www.fototime.com/94E23D0AC147FC1/standard.jpg

.............I just now posted this in a thread in "Cast Boolits" but here it is again. This is the RCBS 38-162-SWC-GC which feeds and shoots like gangbusters in my 38 Super Witness (CZ75 clone). Of course like any other group of guns they're gonna be differences. Mine has fed and fired everything I've fed it so far, but I haven't tried a full WC yet :-)

.................Buckshot

[Linstrum]

My goodness, Rick, that cartridge is pretty enough to stick on the front of a Rolls-Royce as the hood ornament!

You really must have run it through the tumbler with some good polishing compound!


rl779

[chris in va]

I have a Cz85B I bought new about five years ago and it is a 2 to 3-inch at 25 yard shooter using the Lee 356-120-TC

What powder charge do you use to keep it from tumbling? I had the 124gr TC mold and everything but a very low charge would send it sideways. And even then the pattern was trying to keep it on an 8x11 sheet of paper at 25 yards.

[finishman2000]

Boolits not "heads", please.

heads, heads, heads and heads.

[Linstrum]

What powder charge do you use to keep it from tumbling? I had the 124gr TC mold and everything but a very low charge would send it sideways. And even then the pattern was trying to keep it on an 8x11 sheet of paper at 25 yards.

Hi, chris in va, I use the Lyman 46th edition manual for most of my load data for both pistols and rifles. This manual represents several decades of load development work and is one of the best for cast projectile loads.

For my Cz85B I usually use a mild-medium load of right around 6.5 grains Blue Dot with the Lee 356-120-TC. I have varied the powder a bit over the years, but it is around 6.5 gr Blue Dot. I have also used Unique, but I have had problems getting this particular pistol to cycle reliably with that powder and boolit combination. From what I have been told, the Cz75 and Cz85B are the same basic pistol, so if this is true, then the 6.5 grain Blue Dot with 120 gr boolit load should work for the Cz75 9mm pistol.

I have never had any problems with either the Lee TL356-124-TC or the Lee 356-120-TC tumbling and "key-holing" in my Cz85B when I worked up loads for it. The only problem I had with that particular pistol was getting it to cycle reliably but that is because I always start off with minimum loads and work up to the point where the gun works reliably, and then stop at that point. The reason why I stop as soon as things start to work reliably is because usually each combination of bullet, powder type, and primer type for a particular gun has a "sweet spot" where things work best. Loading hotter sometimes leads to problems, especially with cast in 9mm because of the one turn in 10 inches often used for 9mm Parabellum/Luger that is very fast for a .35 caliber pistol. Many other pistols that have a similar bore size, such as the .38 Special, .357 Magnum, and .38 ACP/.38 Super use substantially slower rifling twists of around one turn in 16 inches to one turn in 20 inches. With its very fast one turn in 10 inches, the 9mm has a greater tendency to "jump" or "strip" the rifling with cast projectiles, and I have a Walther P1 that does this quite badly when using cast boolits. It just doesn't like cast projectiles, and when I got a different barrel for it, it didn't change things for the better.


rl780

[jbremount]

I just got back into town! Got the CZ-75b out and I loaded some bullets from my Lee 358-125-RF mold. They were sized .358 and hard lubed. The OAL is about 1.012. As a starting point, I used 2.4 gr of titegroup powder. Yes......2.4 gr of titegroup. I normally use W231 but decided to use the titegroup I had sitting in the closet. According to my Lyman pistol and revolver reloading handbook,(http://i44.tinypic.com/20sytmv.jpg) the min load is 2.6gr of W231 with a 130gr lead bullet,seated to a OAL of 1.016. The Lyman bullet in the reloading handbook, is not the exact same bullet, but similar enough in weight and size to use for minimum starting loads. Anyway, I chonographed my reloads at an average velocity of 901.8 fps. I made some more bullets at 2.2gr of titegroup and they averaged 867.4 fps. Both of the small charges of titegroup powder functioned the gun fine with almost no leading. There was just a hint of leading forward of the chamber area. I will put some rounds on paper and see what the accuracy is like later. Hopefully with the right velocity and the larger sized .358 sized bullets, the accuracy will be good.

Chris, this is what the finished bullets look like: OAL of 1.012
http://i55.photobucket.com/albums/g153/jbremount/9mmreolad.jpg

The sized and lubed cast bullet from Lee 358-125-RF mold:
http://i55.photobucket.com/albums/g153/jbremount/9mmbullet.jpg


The Lee 358-125-RF as cast bullet: weighed 129gr on scale
http://i55.photobucket.com/albums/g153/jbremount/9mmascastbullet.jpg

[mike in co]

chris,

trim a 9mm case about 0.1 short. a fired case works/not sized. fill the case with lead.

chamber the leaded case.

get some soft lead..real soft.

get a pc about 1" long and just under bore dia.

drop it in the muzzle.

with a tight fitting brass rod....start beating on it.....genttly......

one does not want to beat up your gun...so lots of slow medium hits.

over time upset the lead into the throat/bbl and a bit of case area.

rack the slide and pop out the case.
gently tap out the chamber slug.
measure it...

if not filled out..do it again.

you can lube the chamber/throat, but too much will interfere with the fillout.

[chris in va]

he OAL is about 1.012

Good grief that's short! You can do that safely? BTW that's the same exact mold I have, sized the same also.

Thanks Mike, I'll give that a try.

[Cadillo]

...he is shooting too big of a bullet for the chamber.....


cz'S have a great rep for accuracy out of the box.

so what cz do you have ?

consider sizing down( as in get a 9mm mould and not a 38/357 mould) TRY 356....

Listen to Mike on this.

I have some experience with CZ rimfire rifles, and can tell you that their bores are exceptionally tight, which is one reason that they are so very accurate. I had to obtain a .20 cal. cleaning rod to clean my 453 Varmint and 452 American. My .22 cal. rods would not even enter the bore.

That said, the OP is loading the wrong caliber bullet. I think that SAAMI calls for something like a .3555 max bore diameter in 9x19mm. Given that his gun is a CZ, I would imagine that it is quite a bit even tighter than that.

You just can't put 10 lbs. of flour into a 5 lb. bag.

[mike in co]

Good grief that's short! You can do that safely? BTW that's the same exact mold I have, sized the same also.

Thanks Mike, I'll give that a try.

a 125 at 900 fps is not much of a load......
i typically shoot a 124 at 1050 or so( if you are counting ,that is a 130 power factor....nra action shooting, wimpy ipsc load).
and our gb 135 at 1000 or so.

if you are happy with it and it cycles the gun fine.


jbre: what is the case dia just below the crimp ?

mike in co

[robertbank]

What powder charge do you use to keep it from tumbling? I had the 124gr TC mold and everything but a very low charge would send it sideways. And even then the pattern was trying to keep it on an 8x11 sheet of paper at 25 yards.

If your bullets are tumbling in a 9MM your bullets are sized to small. .356 is a minimum for 9MM and I now think .357 works the best. One of our IDPA shooters bought some lead round nose Sierra bullets. Half of them wnet sidways at 10 yards. All were sized .355.

Take Care

Bob

[mike in co]

heads, heads, heads and heads.


some people quit growing, some quit learning.

you are dead when you quit learning and growing.

then there are some that want to make sure that we know they have quit.


have you ever seen the sierra head company ?

have you ever seen berger head company ?

how about the speer head company ?

no ??? me too.


now from SAAMI glossary we have this:
HEAD
The end of the cartridge case in which the primer or priming is inserted and the surface upon which the headstamp identification is imprinted.


so you go right ahead and continue to show your lack of willingness to learn and grow.

mike in co

[chris in va]

Well, somewhat of an update.

Finally got around to shooting a couple hundred of the 358's through my HiPoint carbine. Not only do they not tumble, but accurate enough to chew a ragged hole at 25 yards. I was hitting a steel I-beam (found at the scrap yard!) at 75 yards no problem.

Just for the heck of it, I'll load some of those for the CZ 75 so they *just* chamber and see how it works out. I still think 1.01 is super short, but why not.

[jbremount]

quick update,

I have been doing a few informal tests with the boolits from my Lee 358-125-RF mold and titegroup powders. I am using my CZ-75b and the boolits weigh aproximately 130gr sized to .358 and were air cooled. I initially started with an OAl of 1.010-1.013. The OAL is now about 1.020-1.022. I don't know why, but after the last few range sessions, it appears the gun can shoot a slight longer bullet. I have used as little as 2.2gr and 2.4 gr of titegroup powder. Today I used 2.6 gr of titegroup and chronograph them at an average velocity of 931 fps. I purposely started low and the plan is to eventually work my way to 1000-1050 fps. Anyway, this is a target showing no keyholes. I got a more leading than previous 2.2/2.4gr of titegrougp forward the chamber area, but it cleaned up easy.

So far, from my experiences, this 130gr boolit,sized to .358, in my CZ-75b 9mm gun is quite efficient, utilizing small charges of titegroup powder and easily reaching over 900 fps.

Range is 10 yards, first five grouped well and the remaining three were shooting left,( but demonstrate good clean holes). I called them flyers, but probably flinch/trigger management.
http://i55.photobucket.com/albums/g153/jbremount/IMG_0643.jpg

[chris in va]

I'll have to check the accuracy on my 358's here soon. I was able to hit a 12# square steel I-beam at 75 yards half the time yesterday, so they're a LOT more accurate than my previous stuff. My CZ must be really tight because 1.01 is the maximum I can get it to chamber at. Even that length shows rubbing on the boolit ogive near the case mouth. Not enough to keep it from chambering fully though as I put 300 rounds through it yesterday!

[jbremount]

I'll have to check the accuracy on my 358's here soon. I was able to hit a 12# square steel I-beam at 75 yards half the time yesterday, so they're a LOT more accurate than my previous stuff. My CZ must be really tight because 1.01 is the maximum I can get it to chamber at. Even that length shows rubbing on the boolit ogive near the case mouth. Not enough to keep it from chambering fully though as I put 300 rounds through it yesterday!


What powder/load are you using?

[jbremount]

update:


I had some time to go shooting this weekend. I made up a few 9mm rounds from the boolits I casted earlier from my Lee 358-125-RF mold. In summary, these boolits were all air dropped/hard lubed and sized to .358 with a lyman heater/lubersizer. I loaded about 30-40 rounds with 3.0gr of Titegroup and another 30-40 rounds with 3.3gr of Titegroup. The OAL is the same approx. 1.020-1.023. These are the pictures of the results.


I fired 6 shots at the paper target. The top 4 shots were 3.0gr of Titegroup averaged 968fps and made nice holes in the paper target. The bottom 2 were the same 3.0gr of Titegroup (were probably faster) and did not indicated clean cut holes in the target. They were an indicator of more to come.
http://i55.photobucket.com/albums/g153/jbremount/IMG_0645.jpg





These 5 shots were with 3.3gr of Titegroup averaged 996fps. The first shot near the center was ok, but the rest did not cut clean holes in the paper target. I am calling this tumbling/keyholing, ...... unless there is another reason.
http://i55.photobucket.com/albums/g153/jbremount/IMG_0646.jpg



Shot another 4 shots at a paper target to insure the previous target were correct. I made sure the backing was good and solid/etc. The rounds impacted the target same as previous target, clearly indicating the enlogated holes. I am beginning to become a believer now!
http://i55.photobucket.com/albums/g153/jbremount/IMG_0647.jpg



I shot the next target with a combination of ammo, some 2.6gr Titegroup and some 3.3gr Titegroup. The difference is really demonstrated by this target.
http://i55.photobucket.com/albums/g153/jbremount/IMG_0644.jpg


My conclusion, I need to cast a harder boolit:.....or(maybe there is another element in the equation that I missed)
(1.) The rule of keeping soft cast handgun bullets below 1000fps is a good one.

My air dropped wheel weights boolits fly better at velocites some where at or below 968fps. I will try water quencing the next batch I cast.

[chris in va]

Yup, you'll need to water drop those suckers. I've had no keyholing since switching to that boolit and sizing to 003 over. Next range trip I'll punch paper to find out exactly what accuracy I'm getting with a mid level Bullseye charge.

[MtGun44]

How about using a soft lube? Have you tried this. Hard lubes may contribute to this
behavior, not sealing the bore well like a soft lube.

[robertbank]

Soft lube, .002 over and water quenched and you won't have anymore keyholing or leading with velocities under 1100 fps. You might be better served using 231 or Unique under those bullets as well. I found bullseye to be to fast for the 124 grainers.

Take Care

Bob

[jbremount]

How about using a soft lube? Have you tried this. Hard lubes may contribute to this
behavior, not sealing the bore well like a soft lube.

This is the bullet lube that I am using.(http://cgi.ebay.com/Jakes-Scarlet-High-Speed-Cast-Bullet-Lube-10-Sticks-/380103289064?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item587febe8e8) I use this lube for 38/357, 40S&W and 45ACP. Never had a problem, but I stay under 1000fps also.

I could be wrong, but I don't think it is the lube, as I have used this lube on 30/30 rifles loads and it held up. It is a hard lube and needs a heater to apply, but very elastic, soft enough to dent if you give it a finger nail test. I worked this load up slowly from 800fps range. There was absolutely little to no leading until the speedier boolit began to not follow the grooves and tumble. All barrels will lead when this happens. I am thinking the soft wheel weights boolits are just not hard enough to stay with the fast and shallow twist rifling of this 9mm gun when it gets to approaching to the 1000 fps range. FWIK, the CZ-75B 9mm pistols have an even faster twist rate than the average 9mm pistol.

From the article on CZ-75 (The 6-groove barrel has traditional land-and-groove rifling with a higher-than-standard rate of twist (1 in 9.7).
http://en.wikipedia.org/wiki/Cz_75

[jbremount]

quick update on the water quenched boolits:


The previous air dropped bullets I cast were tumbling as the velocity approached 1000 fps. I cast more and this time I water quenched them. They cured a little over 96 hours before I loaded them. These are the results.

Big grin on my face today!.....the harder bullets are not tumbling and even the velocity has increased!
http://i55.photobucket.com/albums/g153/jbremount/targets/IMG_0657.jpg



http://i55.photobucket.com/albums/g153/jbremount/targets/IMG_0656.jpg


http://i55.photobucket.com/albums/g153/jbremount/targets/IMG_0655.jpg





I was really surprised by the velocity increase. I wanted to see if the velocities were similar to the previous air cooled bullets. This target is with air cooled bullets from the first casting session. The 2.8 gr reloads are just a little faster than the previous 2.6gr reloads. Therefore the chronograph is working ok.
http://i55.photobucket.com/albums/g153/jbremount/targets/IMG_0658.jpg



I now have a few loads worked up that I can use. I have not decided which one, but the 3.3gr of titegroup at 1088fps looks promising for my immediate needs. The 3.7gr of titegroup produced velocities of 1141 fps. I probably can find some use for this load also. IMO, water quenching or some other method of harding the cast boolits is the way to go with fast and high pressure rounds like the 9mm.

[armoredman]

I have been using the TL356-124-2R mould with my CZs with no problem, the CZ short chamber is a curse to reloaders. Looks like you found your solution, congrats, nice groups, sir!

[jbremount]

I have been using the TL356-124-2R mould with my CZs with no problem, the CZ short chamber is a curse to reloaders. Looks like you found your solution, congrats, nice groups, sir!


I am not exactly sure what it is different with the CZ-75b pistol's chamber, but from my experiences, they sure need a short lead cast bullet. Maybe there is a portion of the chamber-to-rifling area that can be polished. Anyway, I am finding that the Lee 38/357 pistol mold (358-125-RF) makes a short bullet that works well with the 9mm - CZ-75b chamber. The mold drops a large diameter bullet of .360-.361 which I size down to .358 diameter. I lube both the bullet's lube groove and the bullets's roll crimping groove. I seat the bullet to just below the roll crimp groove, thus it makes the perfect short bullet. I didn't shoot for small groups as the tumbling had to be fixed first. I'll will shoot for better groups now that I am past the tumbling/key-holing stage of this load development. Therefore.....it ain't over yet!


The larger .358 bullet gives the cartidge an hour glass shape. The neck tension is great and I don't think this bullet will setback easily. No need for an EGW or Lee undersized die here.
http://i55.photobucket.com/albums/g153/jbremount/targets/IMG_0664.jpg

[chris in va]

On a side note I also use these 358's with my HiPoint carbine, just at a longer OAL as the chamber is (deeper?). Very accurate.